Power system switching between charge-discharge function and driving function and electric vehicle comprising the same

ABSTRACT

A power system switching between a charge-discharge function and a driving function and an electric vehicle including the same are provided. The power system includes a power battery; a charge-discharge socket; a bidirectional DC/DC module; a driving control switch connected with the power battery and the bidirectional DC/DC module; a bidirectional DC/AC module connected with the driving control switch and the power battery; a motor control switch connected with the bidirectional DC/AC module and a motor; a charge-discharge control module connected with the bidirectional DC/AC module and the charge-discharge socket; and a controller module configured to establish a path between the power battery and the motor when a current operation mode of the power system is a driving mode, and to establish a path between the charge-discharge socket and the power battery when the current operation mode of the power system is a charge-discharge mode.

FIELD

The present disclosure relates to an electric vehicle field, and moreparticularly to a power system switching between a charge-dischargefunction and a driving function, and an electric vehicle comprising thepower system.

BACKGROUND

With the development of science and technology, fuel vehicles are beingreplaced by environment friendly and energy saving electric vehicles.However, the popularity of the electric vehicles encounters someproblems, among which high driving mileage and fast charging technologyhas become a major problem in the promotion of electric vehicles.

Currently, large-capacity batteries are used in most electric vehicles.However, although these batteries may enhance a battery life of theelectric vehicle, they make a charging time too long. Although aspecialized DC (direct current) charging station may charge a batteryquickly, problems such as high cost and large occupied area make thepopularity of such an infrastructure encounter a certain difficulty.Moreover, because of a limited space of the vehicle, an in-vehiclecharger may not satisfy the requirement of a charging power due to thelimitation of its volume.

A charging solution currently used in the market comprises the followingsolutions.

Solution (1)

As shown in FIGS. 1-2, an in-vehicle charge-discharge device in thissolution mainly comprises a three-phase power transformer 1′, athree-phase bridge circuit 2′ consisting of six thyristor elements, aconstant-voltage control device AUR, and a constant-current controldevice ACR. However, this solution causes a serious waste of space andcost.

Solution (2)

As shown in FIG. 3, an in-vehicle charge-discharge device in thissolution comprises two charge sockets 15′, 16′ to adapt to thesingle-phase/three-phase charging, which increases the cost. A motordriving loop comprises a filtering module consisting of an inductor L1′and a capacitor C1′. When a motor is driven, a loss of a three-phasecurrent is generated when it flows through the filtering module, whichcauses a waste of an electric quantity of a battery. With this solution,during the charge-discharge operation, an inverter 13′ rectifies/invertsan AC (alternating current), and the voltage after therectifying/inverting may not be adjusted, such that a battery operationvoltage range is narrow.

Therefore, most AC charging technologies currently used in the marketare a single-phase charging technology, which has disadvantages of lowcharging power, long charging time, large hardware volume, singlefunction, restriction by voltage levels of different regional grids,etc.

SUMMARY

Embodiments of the present disclosure seek to solve at least one of theproblems existing in the related art to at least some extent.

Accordingly, an object of the present disclosure is to provide a powersystem switching between a charge-discharge function and a drivingfunction, which may charge the electric vehicle with a high power bymeans of a civil or industrial AC grid, such that a user may perform thecharge efficiently, promptly, anytime and anywhere. Moreover, aconstant-voltage control device or a constant-current control device isnot required, thus saving a space and a cost and having a wide batteryoperation voltage range.

Another object of the present disclosure is to provide an electricvehicle.

In order to achieve the above objects, embodiments of an aspect of thepresent disclosure provide a power system switching between acharge-discharge function and a driving function. The power systemincludes: a power battery; a charge-discharge socket; a bidirectionalDC/DC module having a first DC terminal connected with a first terminalof the power battery and a second DC terminal connected with a secondterminal of the power battery, in which the first DC terminal is acommon DC terminal for an input to and an output from the bidirectionalDC/DC module; a driving control switch having a first terminal connectedwith the second terminal of the power battery and a second terminalconnected with a third DC terminal of the bidirectional DC/DC module; abidirectional DC/AC module having a first DC terminal connected with thesecond terminal of the driving control switch and a second DC terminalconnected with the first terminal of the power battery; a motor controlswitch having a first terminal connected with an AC terminal of thebidirectional DC/AC module and a second terminal connected with a motor;a charge-discharge control module having a first terminal connected withthe AC terminal of the bidirectional DC/AC module and a second terminalconnected with the charge-discharge socket; and a controller moduleconnected with the driving control switch, the motor control switch andthe charge-discharge control module respectively, and configured toestablish a path between the power battery and the motor when a currentoperation mode of the power system is a driving mode, and to establish apath between the charge-discharge socket and the power battery when thecurrent operation mode of the power system is a charge-discharge mode.

With the power system switching between the charge-discharge functionand the driving function according to embodiments of the presentdisclosure, the electric vehicle can be charged with a high power bymeans of a civil or industrial AC grid, such that a user may perform thecharge efficiently, promptly, anytime and anywhere, thus saving acharging time. Moreover, a constant-voltage control device or aconstant-current control device is not required, thus saving a space anda cost and having a wide battery operation voltage range.

Moreover, embodiments of another aspect of the present disclosureprovide an electric vehicle including the abovementioned power system.

The electric vehicle can be charged with a high power by means of athree-phase or single-phase current, such that a user may charge theelectric vehicle conveniently, promptly, anytime and anywhere, thussaving a time cost and satisfying the requirement of persons.

Additional aspects and advantages of embodiments of present disclosurewill be given in part in the following descriptions, become apparent inpart from the following descriptions, or be learned from the practice ofthe embodiments of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects and advantages of embodiments of the presentdisclosure will become apparent and more readily appreciated from thefollowing descriptions made with reference to the drawings, in which:

FIG. 1 is a circuit diagram of a conventional in-vehiclecharge-discharge device;

FIG. 2 is a diagram of controlling a conventional in-vehiclecharge-discharge device;

FIG. 3 is a circuit diagram of another conventional in-vehiclecharge-discharge device;

FIG. 4 is a block diagram of a power system switching between acharge-discharge function and a driving function according to anembodiment of the present disclosure;

FIG. 5 is a topological diagram of a power system switching between acharge-discharge function and a driving function according to anembodiment of the present disclosure;

FIG. 6 is a block diagram of a power system switching between acharge-discharge function and a driving function according to anembodiment of the present disclosure;

FIG. 7 is a block diagram of a controller module according to anembodiment of the present disclosure;

FIG. 8 is a diagram showing interfaces of DSP (digital signalprocessing) chips in a controller module to be connected with aperipheral hardware circuit;

FIG. 9 is a flow chart of determining a function of a power systemswitching between a charge-discharge function and a driving functionaccording to an embodiment of the present disclosure;

FIG. 10 is a block diagram of a power system switching between acharge-discharge function and a driving function according to anembodiment of the present disclosure performing a motor driving controlfunction;

FIG. 11 is a flow chart of determining whether to start acharge-discharge function for a power system switching between acharge-discharge function and a driving function according to anembodiment of the present disclosure;

FIG. 12 is a flow chart of controlling a power system switching betweena charge-discharge function and a driving function according to anembodiment of the present disclosure in a charging operation mode;

FIG. 13 is a flow chart of controlling a power system switching betweena charge-discharge function and a driving function according to anembodiment of the present disclosure when the charging of the electricvehicle is finished;

FIG. 14 is a circuit diagram of a connection between an electric vehicleand a power supply apparatus according to an embodiment of the presentdisclosure;

FIG. 15 is a schematic diagram of charging an electric vehicle using twopower systems connected in parallel according to an embodiment of thepresent disclosure;

FIG. 16 is a schematic diagram of a charge-discharge socket according toan embodiment of the present disclosure;

FIG. 17 is a schematic diagram of an off-grid on-load discharge plugaccording to an embodiment of the present disclosure;

FIG. 18 is a block diagram of a power carrier communication system foran electric vehicle according to an embodiment of the presentdisclosure;

FIG. 19 is a block diagram of a power carrier communication device;

FIG. 20 is a schematic diagram of communications between eight powercarrier communication devices and corresponding control devices;

FIG. 21 is a flow chart of a method for receiving data by a powercarrier communication system; and

FIG. 22 is a schematic view of a body of a power system switchingbetween a charge-discharge function and a driving function according toan embodiment of the present disclosure.

DETAILED DESCRIPTION

Reference will be made in detail to embodiments of the presentdisclosure. The same or similar elements and the elements having same orsimilar functions are denoted by like reference numerals throughout thedescriptions. The embodiments described herein with reference todrawings are explanatory, illustrative, and used to generally understandthe present disclosure. The embodiments shall not be construed to limitthe present disclosure.

Various embodiments and examples are provided in the followingdescription to implement different structures of the present disclosure.In order to simplify the present disclosure, certain elements andsettings will be described. However, these elements and settings areonly by way of example and are not intended to limit the presentdisclosure. In addition, reference numerals may be repeated in differentexamples in the present disclosure. This repeating is for the purpose ofsimplification and clarity and does not refer to relations betweendifferent embodiments and/or settings. Furthermore, examples ofdifferent processes and materials are provided in the presentdisclosure. However, it would be appreciated by those skilled in the artthat other processes and/or materials may be also applied. Moreover, astructure in which a first feature is “on” a second feature may includean embodiment in which the first feature directly contacts the secondfeature, and may also include an embodiment in which an additionalfeature is formed between the first feature and the second feature sothat the first feature does not directly contact the second feature.

In the description of the present disclosure, it should be understoodthat, unless specified or limited otherwise, the terms “mounted,”“connected,” and “coupled” and variations thereof are used broadly andencompass such as mechanical or electrical mountings, connections andcouplings, also can be inner mountings, connections and couplings of twocomponents, and further can be direct and indirect mountings,connections, and couplings, which can be understood by those skilled inthe art according to the particular embodiment of the presentdisclosure.

Referring to the following descriptions and drawings, these and otheraspects of the embodiments of the present disclosure will be apparent.In these descriptions and drawings, some specific approaches of theembodiments of the present disclosure are provided, so as to show someways to perform the principle of the embodiments of the presentdisclosure, however it should be understood that the embodiment of thepresent disclosure is not limited thereby. Instead, the embodiments ofthe present disclosure comprise all the variants, modifications andtheir equivalents within the spirit and scope of the present disclosureas defined by the claims.

A power system switching between a charge-discharge function and adriving function and an electric vehicle including the power systemaccording to embodiments of the present disclosure will be describedbelow with reference to the drawings.

As shown in FIG. 4, a power system switching between a charge-dischargefunction and a driving function according to an embodiment of thepresent disclosure includes a power battery 10, a charge-dischargesocket 20, a bidirectional DC/DC module 30, a driving control switch 40,a bidirectional DC/AC module 50, a motor control switch 60, acharge-discharge control module 70 and a controller module 80.

The bidirectional DC/DC module 30 has a first DC terminal al connectedwith a first terminal of the power battery 10 and a second DC terminala2 connected with a second terminal of the power battery 10. The firstDC terminal al is a common DC terminal for an input to and an outputfrom the bidirectional DC/DC module 30. The driving control switch 40has a first terminal connected with the second terminal of the powerbattery 10 and a second terminal connected with a third DC terminal a3of the bidirectional DC/DC module 30. The bidirectional DC/AC module 50has a first DC terminal b1 connected with the second terminal of thedriving control switch 40 and a second DC terminal b2 connected with thefirst terminal of the power battery 10. The motor control switch 60 hasa first terminal connected with an AC terminal c of the bidirectionalDC/AC module 50 and a second terminal connected with a motor M. Thecharge-discharge control module 70 has a first terminal connected withthe AC terminal c of the bidirectional DC/AC module 50 and a secondterminal connected with the charge-discharge socket 20. The controllermodule 80 is connected with the driving control switch 40, the motorcontrol switch 60 and the charge-discharge control module 70respectively, and configured to establish a path between the powerbattery 10 and the motor M when a current operation mode of the powersystem is a driving mode, and to establish a path between thecharge-discharge socket 20 and the power battery 10 when the currentoperation mode of the power system is a charge-discharge mode.

Further, in some embodiments, the current operation mode of the powersystem may include a driving mode and a charge-discharge mode. When thecurrent operation mode of the power system is the driving mode, thecontroller module 80 controls the driving control switch 40 to turn onto stop the bidirectional DC/DC module 30, controls the motor controlswitch 60 to turn on to drive the motor M normally, and controls thecharge-discharge control module 70 to turn off. It should be noted that,although in some embodiments, the motor control switch 60 in FIG. 5includes three switches connected with a three-phase input to the motor,in other embodiments, the motor control switch 60 may also include twoswitches connected with a two-phase input to the motor, or even oneswitch, as long as the control on the motor may be realized. Therefore,other embodiments will not be described in detail herein.

When the current operation mode of the power system is thecharge-discharge mode, the controller module 80 controls the drivingcontrol switch 40 to turn off to start the bidirectional DC/DC module30, controls the motor control switch 60 to turn off to remove the motorM, and controls the charge-discharge control module 70 to turn on, suchthat an external power source may charge the power battery 10 normally.The first DC terminal al and the third DC terminal a3 of thebidirectional DC/DC module 30 are connected with a positive terminal anda negative terminal of a DC bus respectively.

In one embodiment, as shown in FIG. 5, the power system switchingbetween the charge-discharge function and the driving function furtherincludes a first pre-charging control module 101. The first pre-chargingcontrol module 101 has a first terminal connected with the secondterminal of the power battery 10 and a second terminal connected withthe second DC terminal a2 of the bidirectional DC/DC module 30, andconfigured to pre-charge a capacitor C1 in the bidirectional DC/DCmodule 30 and a bus capacitor C0 connected between the first DC terminalal and the third DC terminal a3 of the bidirectional DC/DC module 30.The first pre-charging control module 101 includes a first switch K1, afirst resistor R1 and a second switch K2. The first switch K1 has afirst terminal connected with the second DC terminal a2 of thebidirectional DC/DC module 30. The first resistor R1 has a firstterminal connected with a second terminal of the first switch K1 and asecond terminal connected with the second terminal of the power battery10. The second switch K2 is connected in parallel with the firstresistor R1 and the first switch K1 which are connected in series. Whenthe power system starts, the controller module 80 controls the firstswitch K1 to turn on to pre-charge the capacitor C1 in the bidirectionalDC/DC module 30 and the bus capacitor C0; and when a voltage across thebus capacitor C0 is a predetermined multiple of a voltage of the powerbattery 10, the controller module 80 controls the first switch K1 toturn off and controls the second switch K2 to turn on.

As shown in FIG. 5, the bidirectional DC/DC module 30 includes a firstswitching transistor Q1, a second switching transistor Q2, a first diodeD1, a second diode D2, a first inductor L1 and a first capacitor C1. Thefirst switching transistor Q1 and the second switching transistor Q2 areconnected in series, and connected between the first DC terminal al andthe third DC terminal a3 of the bidirectional DC/DC module 30, andcontrolled by the controller module 80. A first node A is definedbetween the first switching transistor Q1 and the second switchingtransistor Q2. The first diode D1 is connected with the first switchingtransistor Q1 in inverse-parallel. The second diode D2 is connected withthe second switching transistor Q2 in inverse-parallel. The firstinductor L1 has a first terminal connected with the first node A and asecond terminal connected with the second terminal of the power battery10. The first capacitor C1 has a first terminal connected with thesecond terminal of the first inductor L1 and a second terminal connectedwith the first terminal of the power battery 10.

Moreover, in some embodiments, as shown in FIG. 5, the power systemswitching between the charge-discharge function and the driving functionfurther includes a leakage current reducing module 102. The leakagecurrent reducing module 102 is connected between the first DC terminalal and the third DC terminal a3 of the bidirectional DC/DC module 30.Specifically, the leakage current reducing module 102 includes a secondcapacitor C2 and a third capacitor C3. The second capacitor C2 has afirst terminal connected with a first terminal of the third capacitor C3and a second terminal connected with the first DC terminal al of thebidirectional DC/DC module 30, the third capacitor C3 has a secondterminal connected with the third DC terminal a3 of the bidirectionalDC/DC module 30, and a second node B is defined between the secondcapacitor C2 and the third capacitor C3.

Generally, a leakage current is large in an inverter and grid systemwithout transformer isolation. Therefore, with the power systemaccording to embodiments of the present disclosure, the leakage currentreducing module 102 is connected between the positive terminal and thenegative terminal of the DC bus, thus reducing the leakage currenteffectively. The leakage current reducing module 102 includes twocapacitors C2 and C3 of the same type, the capacitor C2 is connectedbetween the negative terminal of the DC bus and a three-phase AC neutralpoint potential, the capacitor C3 is connected between the positiveterminal of the DC bus and the three-phase AC neutral point potential,and a high-frequency current may be fed back to a DC side when the powersystem operates, thus effectively reducing a high-frequency leakagecurrent generated when the power system operates.

In one embodiment, as shown in FIG. 5, the power system switchingbetween the charge-discharge function and the driving function furtherincludes a filtering module 103, a filtering control module 104, anEMI-filter module 105 and a second pre-charging control module 106.

The filtering module 103 is connected between the bidirectional DC/ACmodule 50 and the charge-discharge control module 70. Specifically, thefiltering module 103 includes inductors L_(A), L_(B), L_(C) andcapacitors C4, C5, C6, and the bidirectional DC/AC module 50 maycomprise six IGBTs (insulated gate bipolar transistor), a connectionpoint between an upper IGBT and a lower IGBT is connected with thefiltering module 103 and the motor control switch 60 via a power busrespectively.

As shown in FIG. 5, the filtering control module 104 is connectedbetween the second node B and the filtering module 103, and controlledby the controller module 80. When the current operation mode of thepower system is the driving mode, the controller module 80 controls thefiltering control module 104 to turn off. The filtering control module104 may be a contactor relay, and consists of a contactor K10. TheEMI-filter module 105 is connected between the charge-discharge socket20 and the charge-discharge control module 70. It should be noted that,the position of the contactor K10 in FIG. 5 is merely exemplary. Inother embodiments, the contactor K10 may be located at other positions,provided that the filtering module 103 may be turned off using thecontactor K10. For example, in another embodiment, the contactor K10 mayalso be connected between the bidirectional DC/AC module 50 and thefiltering module 103.

The second pre-charging control module 106 is connected with thecharge-discharge control module 70 in parallel and configured topre-charge capacitors C4, C5, C6 in the filtering module 103. The secondpre-charging control module 106 includes three resistors R_(A), R_(B),R_(C) and a three-phase pre-charging switch K9.

In one embodiment, as shown in FIG. 5, the charge-discharge controlmodule 70 includes a three-phase switch K8 and/or a single-phase switchK7 configured to implement a three-phase charge-discharge or asingle-phase charge-discharge.

In other words, in some embodiments, when the power system starts, thecontroller module 80 controls the first switch K1 to turn on topre-charge the first capacitor C1 in the bidirectional DC/DC module 30and the bus capacitor C0; and when the voltage across the bus capacitorC0 is a predetermined multiple of the voltage of the power battery 10,the controller module 80 controls the first switch K1 to turn off andcontrols the second switch K2 to turn on. In this way, the bidirectionalDC/DC module 30 and the large-capacity bus capacitor C0 directlyconnected between power buses (i.e. DC buses) constitute main componentsfor implementing a battery activation technology at a low temperature,and are configured to transfer the electric energy of the power battery10 to the large-capacity bus capacitor C0 via the bidirectional DC/DCmodule 30, and to transfer the electric energy stored in thelarge-capacity bus capacitor C0 to the power battery 10 via thebidirectional DC/DC module 30 (i.e. charge the power battery 10).Therefore, the circulating charge and discharge of the power battery 10makes the temperature of the power battery 10 rise to an optimumoperation temperature range.

When the current operation mode of the power system is the driving mode,the controller module 80 controls the driving control switch 40 to turnon to stop the bidirectional DC/DC module 30, controls the motor controlswitch 60 to turn on to drive the motor M normally, and controls thecharge-discharge control module 70 to turn off. In this way, a DC fromthe power battery 10 is inverted into an AC by means of thebidirectional DC/AC module 50, and the AC is transmitted to the motor M.The motor M can be controlled by a revolving transformer decodertechnology and a space vector pulse width modulation (SVPWM) controlalgorithm.

When the current operation mode of the power system is thecharge-discharge mode, the controller module 80 controls the drivingcontrol switch 40 to turn off to start the bidirectional DC/DC module30, controls the motor control switch 60 to turn off to remove the motorM, and controls the charge-discharge control module 70 to turn on, suchthat an external power source such as a three-phase power source or asingle-phase power source may charge the power battery 10 via thecharge-discharge socket 20 normally. In other words, by detecting acharge connection signal, a type of an AC grid and relevant informationon whole vehicle battery management, a controllable rectificationfunction may be performed with aid of the bidirectional DC/AC module 50,and the power battery 10 may be charged by the single-phase power sourceand/or the three-phase power source with aid of the bidirectional DC/ACmodule 50 and the bidirectional DC/DC module 30.

With the power system switching between the charge-discharge functionand the driving function according to embodiments of the presentdisclosure, the electric vehicle can be charged with a high power bymeans of a civil or industrial AC grid, such that a user may perform thecharge efficiently, promptly, anytime and anywhere, thus saving acharging time. Moreover, a constant-voltage control device or aconstant-current control device is not required, thus saving a space anda cost and having a wide battery operation voltage range.

In addition, in some embodiments, as shown in FIG. 6, the power systemswitching between the charge-discharge function and the driving functionfurther includes a high-voltage distribution box 90, a dashboard 107, abattery manager 108 and a vehicle signal detector 109. The drivingcontrol module 40, the first switch K1 and the second switch K2 may bedisposed in the high-voltage distribution box 90.

In one embodiment, as shown in FIG. 7, the controller module 80 includesa control panel 201 and a driving panel 202. A control module on thecontrol panel 201 comprises two high-speed digital signal processingchips (i.e., DSP1 and DSP2). The control module on the control panel 201is connected and communicated with a vehicle information interface 203.The control module on the control panel 201 is configured to receive abus voltage sampling signal, an IPM protection signal and an IGBTtemperature sampling signal output from a driving module on the drivingpanel 202, and to output a pulse width modulation (PWM) signal to thedriving module.

As shown in FIG. 8, the DSP1 is mainly configured to control and theDSP2 is configured to sample information. A sampling unit in the DSP1outputs sampling signals comprising a throttle signal, a bus voltagesampling signal, a brake signal, a DC-side voltage sampling signal, aHall V-phase signal of a current of the motor M, a Hall W-phase signalof the current of the motor M, a Hall U-phase signal of a chargingcontrol current, a Hall V-phase signal of the charging control current,a Hall W-phase signal of the charging control current, a Hall signal ofa DC current, a U-phase signal of an inverter voltage, a V-phase signalof the inverter voltage, a W-phase signal of the inverter voltage, aU-phase signal of a grid voltage, a V-phase signal of the grid voltage,a W-phase signal of the grid voltage, an inverting U-phase capturingsignal, a grid U-phase capturing signal, etc. A switch control unit inthe DSP1 outputs an A-phase switch signal of the motor, a B-phase switchsignal of the motor, an A-phase switch signal of the grid, a B-phaseswitch signal of the grid, a C-phase switch signal of the grid, athree-phase pre-charging switch signal, a contactor relay signal, etc. Adriving unit in the DSP1 outputs an A-phase PWM1 signal, an A-phase PWM2signal, a B-phase PWM1 signal, a B-phase PWM2 signal, a C-phase PWM1signal, a C-phase PWM2 signal, a DC-phase PWM1 signal, a DC-phase PWM2signal, an IPM protection signal, etc. In addition, the DSP1 also hasother functions such as a revolving signal output control function, aserial communication function, a hardware protection function, a CANcommunication function and a gear control function. A sampling unit inthe DSP2 outputs a monitoring signal for a power supply, a monitoringsignal for a power source, a first throttle signal, a second brakesignal, a second throttle signal, a first brake signal, an analogtemperature signal of the motor, a leakage sensor signal, a temperaturesignal of a radiator, a temperature sampling signal of an inductor atthe DC side, a temperature sampling signal of a V-phase inductor, atemperature sampling signal of a U-phase inductor, a temperaturesampling signal of a W-phase inductor, a discharging PWM voltagesampling signal, a read signal of a tilt sensor, a chip select signal ofthe tilt sensor, a W-phase IGBT temperature sampling signal, a U-phaseIGBT temperature sampling signal, a buck-boost-phase IGBT temperaturesampling signal, a V-phase IGBT temperature sampling signal, a motortemperature switch signal, a single/three-phase toggle switch signal,etc. A charge-discharge control unit in the DSP2 outputs acharge-discharge switch signal, a dormant signal, a discharging PWMsignal, a BMS signal of a battery manager, a charge-discharge outputcontrol signal, a CP signal, a CC signal, etc. The DSP2 also has otherfunctions such as a CAN communication function and a serialcommunication function.

Accordingly, the power system switching between the charge-dischargefunction and the driving function according to embodiments of thepresent disclosure combines a motor driving function, a vehicle controlfunction, an AC charging function, a grid connection function, anoff-grid on-load function and a vehicle-to-vehicle charging function.Moreover, the power system does not combine various functional modulessimply and physically, but based on a motor driving control system,makes use of some peripheral devices to implement the diversification ofthe functions of the system, thus saving space and cost to a maximumextent and improving a power density.

Specifically, functions of the power system switching between thecharge-discharge function and the driving function are simply describedbelow.

1. Motor Driving Function

ADC from the power battery 10 is inverted into an AC by means of thebidirectional DC/AC module 50, and the AC is transmitted to the motor M.The motor M can be controlled by a revolving transformer decodertechnology and a space vector pulse width modulation (SVPWM) controlalgorithm.

In other words, when the power system is powered to operate, as shown inFIG. 9, a process of determining a function of the power system includesthe following steps.

At step 901, the power system is powered.

At step 902, it is determined whether there is a charge connectionsignal.

If there is a charge connection signal, step 903 is executed;

otherwise, step 904 is executed.

At step 903, the power system enters a charge-discharge control process.In one embodiment, a throttle signal, a gear signal and a brake signalare also determined. When the throttle is zero, and the electric vehicleis in N gear, and the electric vehicle is braked by a handbrake, and thecharge connection signal (i.e. a CC signal) is effective (i.e. thecharge-discharge socket 20 is connected with a charge connectiondevice), the power system enters the charge-discharge control process.

At step 904, the power system enters a vehicle control process.

After the power system enters the vehicle control process at step 904,the controller module 80 controls the motor control switch 60 to turnon, and informs the battery manager 108 via a CAN communication. Thebattery manager 108 controls the high-voltage distribution box 90 topre-charge the first capacitor C1 and the bus capacitor C0, and then thecontroller module 80 detects a bus voltage 187 and determines whetherthe pre-charge is successful. If the pre-charge is successful, thecontroller module 80 informs the battery manager 108 to control thedriving control switch 40 to turn on, such that the power system entersthe driving mode; and the controller module 80 samples the vehicleinformation and drives the motor M via a comprehensive judgment process.

The motor driving control function is performed as follows. As shown inFIG. 10, the controller module 80 sends a PWM signal so as to controlthe bidirectional DC/AC module 50 to invert the DC from the powerbattery 10 into the AC and transmit the AC to the motor M. Subsequently,the controller module 80 solves a rotor location via a revolver andsamples the bus voltage and B-phase and C-phase currents of the motor soas to make the motor M operate precisely. In other words, the controllermodule 80 adjusts the PWM signal according to the B-phase and C-phasecurrent signals of the motor sampled by a current sensor and feedbackinformation from the revolver, such that the motor M may operateprecisely.

Thus, by sampling the throttle, brake and gear information of the wholevehicle by a communication module and determining a current operationstate of the vehicle, an accelerating function, a decelerating functionand an energy feedback function can be implemented, such that the wholevehicle can operates safely and reliably under any condition, thusensuring the safety, dynamic performance and comfort of the vehicle.

2. Charge-Discharge Function (1) Connection Confirmation and Start ofCharge-Discharge Function

As shown in FIG. 11, a process of determining whether to start thecharge-discharge function of the power system includes the followingsteps.

At step 1101, the physical connection between the charge-dischargeconnection device and the charge-discharge socket is finished, and thepower source is normal.

At step 1102, a power supply apparatus determines whether the chargeconnection signal (i.e. the CC signal) is normal, if yes, step 1103 isexecuted; if no, step 1102 is re-executed for another determining.

At step 1103, the power supply apparatus determines whether a voltage ata CP detecting point is 9V. If yes, step 1106 is executed; if no, step1102 is re-executed for another determining. 9V is a predetermined valueand is just exemplary.

At step 1104, the controller module determines whether the chargeconnection signal (i.e. the CC signal) is normal. If yes, step 1105 isexecuted; if no, step 1104 is re-executed for another determining.

At step 1105, the charge connection signal and a charge indicator lampsignal are pulled down.

At step 1106, the power system enters the charge-discharge function.

As shown in FIG. 12, a process of controlling the power system in acharging mode includes following steps.

At step 1201, it is determined whether the power system is completelystarted after being powered. If yes, step 1202 is executed; if no, step1201 is re-executed for another determining.

At step 1202, a resistance at a CC (charge connection) detecting pointis detected, so as to determine a capacity of the charge connectiondevice.

At step 1203, it is determined whether a PWM signal with a constant dutyratio is detected at the CP detecting point. If yes, step 1204 isexecuted; if no, step 1205 is executed.

At step 1204, a message indicating the charge connection is normal andthe charge is prepared is sent out and a message indicating BMS permitsthe charge and a charge contactor is turned on is received, and step1206 is executed.

At step 1205, a fault occurs in the charge connection.

At step 1206, the controller module turns on an internal switch.

At step 1207, it is determined whether an external charging apparatusdoes not send a PWM wave in a predetermined time such as 1.5 seconds. Ifyes, step 1208 is executed; if no, step 1209 is executed.

At step 1208, it is determined that the external charging apparatus isan external national standard charging post and the PWM wave is not sentout during the charge.

At step 1209, the PWM wave is sent to the power supply apparatus.

At step 1210, it is determined whether an AC input is normal in apredetermined time such as 3 seconds. If yes, step 1213 is executed; ifno, step 1211 is executed.

At step 1211, a fault occurs in an AC external charging apparatus.

At step 1212, the fault is processed.

At step 1213, the power system enters the charging stage.

In other words, as shown in FIGS. 11-12, after the power supplyapparatus and the controller module 80 detect themselves and no faultoccurs therein, the capacity of the charge connection device may bedetermined by detecting a resistance of the CC signal, and it isdetermined whether the charge-discharge connection device is connectedtotally by detecting the CP signal. After it is determined that thecharge-discharge connection device is connected totally, the messageindicating the charge connection is normal and the charge is prepared issent out, and the battery manager 108 controls the high-voltagedistribution box 90 to turn on the first switch K1 so as to pre-chargethe first capacitor C1 and the bus capacitor C0. After the pre-charge,the first switch K1 is turned off and the second switch K2 is turned on.The controller module 80 receives the message indicating BMS permits thecharge and the second switch K2 is turned on, and thus thecharge-discharge is prepared, i.e., functions such as the AC chargingfunction (G to V, grid to vehicle), the off-grid on-load function (V toL, vehicle to load), the grid connection function (V to G, vehicle togrid) and the vehicle-to-vehicle charging function (V to V, vehicle tovehicle), may be set via the dashboard.

(2) AC Charging Function (G to V)

When the power system receives a charging instruction from thedashboard, the controller module 80 determines a minimum chargingcurrent among a maximum charging current allowed by the battery manager80, a maximum power supply current of the power supply apparatus and arated current of the charge-discharge connection device (i.e. thecharge-discharge socket 20), and selects relevant charging parametersautomatically. Moreover, the power system samples the AC transmitted bythe power supply apparatus via a grid voltage sampling module 183, so asto obtain a sampling value. The controller module 80 solves an effectivevalue of an AC voltage according to the sampling value and determines anAC frequency by capturing. A type of the AC can be determined accordingto the effective value of the AC voltage and the AC frequency, andcontrol parameters can be selected according to the type of the AC.After the control parameters are determined, the controller module 80controls the three-phase pre-charging switch K9 in the secondpre-charging module 106 and the contactor K10 in the filtering controlmodule 104 to turn on, so as to charge the bus capacitor C0 at a DCside. The controller module 80 samples the bus voltage 187, i.e. thevoltage across the bus capacitor C0. When the bus voltage reaches apredetermined control parameter, for example, the bus voltage is apredetermined multiple of the voltage of the power battery 10, thecontroller module 80 controls the three-phase switch K8 to turn on andthe three-phase switch K9 to turn off. According to selected parameters,the controller module 80 sends the PWM signal to control thebidirectional DC/AC module 50 to rectify an AC to obtain a DC. Then, thecontroller module 80 controls the bidirectional DC/DC module 30 toadjust the voltage of the DC according to the voltage of the powerbattery 10, and finally the DC is transmitted to the power battery 10.During the above process, the controller module 80 performs aclosed-loop current control on the power system according to thedetermined target charging current and phase currents fed back from acurrent sampling module 184, and finally the power battery 10 ischarged. Thus, by detecting a charge connection signal, a type of an ACgrid and relevant information on whole vehicle battery management, acontrollable rectification function may be performed with aid of thebidirectional DC/AC module 50, and the power battery 10 may be chargedby the single-phase power source and/or the three-phase power sourcewith aid of the bidirectional DC/DC module 30 and the bidirectionalDC/AC module 50.

(3) Off-Grid On-Load Function (V to L)

When the power system receives a V to L instruction from the dashboard,it is first determined whether a state of charge (SOC) of the powerbattery 10 is in an allowable discharging range. If yes, a type of anoutput voltage is selected according to the V to L instruction. Amaximum output power is selected intelligently and controls parametersare given according to the rated current of the charge-dischargeconnection device, and then the power system enters a control process.First, the controller module 80 controls the three-phase switch K8 andthe contactor K10 to turn on and sends the PWM signal to control thebidirectional DC/DC module 30 to adjust the voltage of the DC accordingto the voltage of the power battery and a given output voltage. Afterthe voltage adjusted by the bidirectional DC/DC module 30 reaches atarget value, the DC is transmitted to the bidirectional DC/AC module 50to be inverted into the AC, and electric apparatuses may be powered bythe AC directly via a dedicated charge socket. During the above process,the controller module 80 performs the adjustment according to a feedbackof the voltage sampling module 183, so as to ensure safe and reliableoperation of a load.

In other words, after the power system is powered, when the V to Linstruction from the dashboard and a required type of an output voltageare received, the charge connection signal and relevant information onwhole vehicle battery management are detected, the DC/DC voltageconversion is performed according to the voltage of the power battery,and the DC is inverted into the AC by means of the bidirectional DC/ACmodule 50, thus outputting a stable single-phase/three-phase AC voltage.

(4) Grid connection function (V to G)

When the power system receives a V to G instruction from the dashboard,it is first determined whether the state of charge (SOC) of the powerbattery 10 is in the allowable discharging range. If yes, a type of anoutput voltage is selected according to the V to G instruction. Amaximum output power is selected intelligently and controls parametersare given according to the rated current of the charge-dischargeconnection device, and the power system enters a control process. First,the controller module 80 controls the three-phase switch K8 and thecontactor K10 to turn on and sends the PWM signal to control thebidirectional DC/DC module 30 to adjust the voltage of the DC accordingto the voltage of the power battery and the given output voltage. Then,the DC is transmitted to the bidirectional DC/AC module 50 to beinverted into the AC. During the above process, the controller module 80performs the closed-loop current control on the power system accordingto a predetermined target discharging current and the phase currents fedback from the current sampling 184, so as to implement the gridconnection discharging.

In other words, after the power system is powered, when the V to Ginstruction from the dashboard is received, the charge connectionsignal, the type of the AC grid and relevant information on wholevehicle battery management are detected, the DC/DC voltage conversion isperformed according to the voltage of the power battery, and the DC isinverted into the AC by means of the bidirectional DC/AC module 50, andthus the vehicle supplies the single-phase/three-phase AC to the grid.

(5) Vehicle-to-vehicle charging function (V to V)

The V to V function requires a dedicated connection plug. When the powersystem determines that the charge connection signal (i.e. CC signal) iseffective and the connection plug is a dedicated charge plug for the Vto V function by detecting a level of the connection plug, the powersystem is prepared for an instruction from the dashboard. For example,assuming vehicle A charges vehicle B, the vehicle A is set in adischarging state, i.e. the vehicle A is set to perform the off-gridon-load function, and the vehicle B is set in an AC charging state. Thecontroller module in vehicle A sends the message indicating the chargeconnection is normal and the charge is prepared to the battery manager.The battery manager controls a charge-discharge circuit to perform thepre-charging, and sends the message indicating the charge is permittedand the charging contactor is turned on to the controller module afterthe pre-charging is finished. Then, the power system performs thedischarging function and sends the PWM signal. After the vehicle Breceives the charging instruction, the power system therein detects a CPsignal which determines that the vehicle A is prepared to supply power,and the controller module 80 sends a normal connection message to thebattery manager. After receiving the message, the battery manager 108finishes the pre-charging process and informs the controller module thatthe whole power system is prepared for the charge. Then, thevehicle-to-vehicle charging function (V to V) starts, and thus vehiclescan charge each other.

In other words, after the power system is powered, when the V to Vinstruction from the dashboard is received, the charge connection signaland relevant information on whole vehicle battery management aredetected, and the vehicle is set in an AC power output state and sendsthe CP signal by simulating an external charging apparatus, so as tocommunicate with the vehicle to be charged. With the vehicle, the DC/DCvoltage conversion is performed according to the voltage of the powerbattery, and the DC is inverted into the AC by means of thebidirectional DC/AC module 50, and thus the vehicle can charge anothervehicle with the single-phase/three-phase AC.

In one embodiment, as shown in FIG. 13, a process of controlling thepower system when the charging of the electric vehicle is finishedincludes the following steps.

At step 1301, the power supply apparatus turns off a power supply switchto stop outputting the AC, and step 1305 is executed.

At step 1302, the controller module stops the charge and performs theunloading, and step 1303 is executed.

At step 1303, after the unloading is finished, the internal switch isturned off and a charge finishing message is sent out.

At step 1304, a power-off request is sent out.

At step 1305, the charge is finished.

As shown in FIG. 14, a power supply apparatus 301 is connected with avehicle plug 303 of an electric vehicle 1000 via a power supply plug302, so as to charge the electric vehicle 1000. The power system of theelectric vehicle 1000 detects a CP signal at a detecting point 3 anddetects a CC signal at a detecting point 4, and the power supplyapparatus 301 detects the CP signal at a detecting point 1 and detectsthe CC signal at a detecting point 2. After the charge is finished, theinternal switches S2 in both the power supply plug 302 and the vehicleplug 303 are controlled to turn off.

In another embodiment, a plurality of power systems connected inparallel can be used in the electric vehicle to charge the powerbattery. For example, two power systems connected in parallel are usedto charge the power battery, and the two power systems use a commoncontroller module.

In this embodiment, as shown in FIG. 15, a charging system for theelectric vehicle includes a power battery 10, a first charging branch401, a second charging branch 402 and a controller module 80. Each ofthe first charging branch 401 and the second charging branch 402includes a charge-discharge socket 20, a bidirectional DC/DC module 30,a bus capacitor C0, a bidirectional DC/AC module 50, a filtering module103, a charge-discharge control module 70 and a second pre-chargingmodule 106. Moreover, each of the first charging branch 401 and thesecond charging branch 402 further includes a fuse FU. The power battery10 is connected with the first charging branch 401 via the firstpre-charging control module 101, and connected with the second chargingbranch 402 via the first pre-charging control module 101. The controllermodule 80 is connected with the first charging branch 401 and the secondcharging branch 402 respectively, and configured to control the grid tocharge the power battery 10 via the first charging branch 401 and thesecond charging branch 402 respectively when receiving a chargingsignal.

In addition, an embodiment of the present disclosure provides a methodfor controlling charging an electric vehicle. The method includesfollowing steps.

At step 1, when determining that a first charging branch is connectedwith a power supply apparatus via a charge-discharge socket and a secondcharging branch is connected with the power supply apparatus via thecharge-discharge socket, a controller module sends a charge connectionsignal to a battery manager.

At step 2, after receiving the charge connection signal sent from thecontroller module, the battery manager detects and determines whether apower battery needs to be charged, if yes, a next step is executed.

At step 3, the battery manager sends a charging signal to the controllermodule.

At step 4, after receiving the charging signal, the controller modulecontrols the grid to charge the power battery via the first chargingbranch and the second charging branch respectively.

With the charging system for the electric vehicle and the method forcontrolling charging the electric vehicle according to the aboveembodiments of the present disclosure, the controller module controlsthe grid to charge the power battery via the first charging branch andthe second charging branch respectively, such that a charging power ofthe electric vehicle is increased and a charging time is shortenedgreatly, thus implementing a fast charge and saving a time cost.

In some embodiments, the power system switching between thecharge-discharge function and the driving function has a widecompatibility and performs a single-phase/three-phase switchingfunction, and thus is adapted to various power grids of differentcountries.

Specifically, as shown in FIG. 16, the charge-discharge socket 20 has afunction of switching between two charging sockets (such as a UnitedStates standard charging socket and a European standard chargingsocket). The charge-discharge socket 20 includes a single-phase chargingsocket 501 such as the United States standard charging socket, athree-phase charging socket 502 such as the European standard chargingsocket and two high-voltage contactors K503 and K504. ACC terminal, a CPterminal and a PE terminal are common terminals for the single-phasecharging socket 501 and the three-phase charging socket 502. Thesingle-phase charging socket 501 has an L-phase wire and an N-phase wireconnected with an A-phase wire and a B-phase wire of the three-phasecharging socket 502 via the contactors K503 and K504 respectively. Whenreceiving a single-phase charge-discharge instruction, the controllermodule 80 controls the contactors K503 and K504 to turn on, such thatthe A-phase and B-phase wires of the three-phase charging socket 502 areconnected with the L-phase and N-phase wires of the single-phasecharging socket 501 respectively. The three-phase charging socket 502does not operate, and instead of the L-phase and N-phase wires of thesingle-phase charging socket 501, the A-phase and B-phase wires of thethree-phase charging socket 502 are connected with the charge plug, andthus the controller module 80 can perform the single-phase chargingfunction normally.

Alternatively, as shown in FIG. 5, a standard 7-core socket is used andthe single-phase switch K7 is added between the N-phase and B-phasewires. When receiving the single-phase charge-discharge instruction, thecontroller module 80 controls the single-phase switch K7 to turn on soas to connect the B-phase wire with the N-phase wire. Then, the A-phaseand B-phase wires are used as the L-phase and N-phase wiresrespectively, and the connection plug should be a dedicated connectionplug or a connection plug whose B-phase and C-phase wires are not used.

In other words, in some embodiments, the power system detects a voltageof the grid via the controller module 80 and determines the frequencyand the single-phase/three-phase of the grid by calculation, so as toobtain the type of the grid. Then, the controller module 80 selectsdifferent control parameters according to a type of the charge-dischargesocket 20 and the type of the grid. Furthermore, the controller module80 controls the bidirectional DC/AC module 50 to rectify the ACcontrollably to obtain the DC and controls the bidirectional DC/DCmodule 30 to adjust the voltage of the DC according to the voltage ofthe power battery. Finally, the DC is transmitted to the power battery10.

In another embodiment, as shown in FIG. 17, an off-grid on-loaddischarging socket includes two-core, three-core and four-core socketsconnected with a charge plug, and is configured to output single-phase,three-phase and four-phase current.

FIG. 18 is a block diagram of a power carrier communication system foran electric vehicle according to an embodiment of the presentdisclosure.

As shown in FIG. 18, the power carrier communication system 2000includes a plurality of control devices 110, a vehicle power cable 120and a plurality of power carrier communication devices 130.

Specifically, each of the control devices 110 has a communicationinterface, in which the communication interface may be, for example, butis not limited to, a serial communication interface SCI. The vehiclepower cable 120 supplies power to the control devices 110, and thecontrol devices 110 communicate with each other via the vehicle powercable 120. The power carrier communication devices 130 correspond to thecontrol devices 110 respectively, and the control devices 110 areconnected with corresponding power carrier communication devices 130 viatheir own communication interfaces respectively, and the power carriercommunication devices 130 are connected with each other via the vehiclepower cable 120. The power carrier communication devices 130 obtain acarrier signal from the vehicle power cable 120 so as to demodulate thecarrier signal and send the demodulated carrier signal to thecorresponding control device 110, and also receive and demodulateinformation sent from the corresponding control device 110 and send thedemodulated information to the vehicle power cable 120.

With reference to FIG. 18, the plurality of control devices 110 includea control device 1 to a control device N (N is larger than or equal to 2and is an integer). The plurality of power carrier communication devices130 corresponding to the plurality of control devices 110 comprise apower carrier communication device 1 to a power carrier communicationdevice N. For example, when the control device 1 needs to becommunicated with the control device 2, the control device 2 first sendsa carrier signal to the power carrier communication device 2, and thepower carrier communication device 2 demodulates the carrier signal andsends the demodulated carrier signal to the vehicle power cable 120.Then, the power carrier communication device 1 obtains and demodulatesthe carrier signal from the vehicle power cable 120, and sends thedemodulated carrier signal to the control device 1.

As shown in FIG. 19, each of the power carrier communication devices 130includes a coupler 131, a filter 133, an amplifier 134 and a modem 132connected sequentially.

Further, as shown in FIG. 20, the plurality of power carriercommunication devices 130, such as eight power carrier communicationdevices 1-8, are connected with a gateway 300 via a vehicle power cablebundle 121 and a vehicle power cable bundle 122, and each power carriercommunication device corresponds to one control device. For example, thepower carrier communication device 1 corresponds to a transmissioncontrol device 111, the power carrier communication device 2 correspondsto an engine control device 112, the power carrier communication device3 corresponds to an active suspension device 113, the power carriercommunication device 4 corresponds to an air-conditioner control device114, the power carrier communication device 5 corresponds to an air bag115, the power carrier communication device 6 corresponds to a dashboarddisplay 116, the power carrier communication device 7 corresponds to afault diagnosis device 117, and the power carrier communication device 8corresponds to an illumination device 118.

In this embodiment, as shown in FIG. 21, a method for receiving data bya power carrier communication system includes following steps.

At step 2101, the system is powered to start and a system program entersa state in which data is received from a vehicle power cable.

At step 2102, it is determined whether there is a carrier signal andwhether the carrier signal is correct, if yes, step 2103 is executed; ifno, step 2104 is executed.

At step 2103, the system starts to receive the data sent from thevehicle power cable, and step 2105 is executed.

At step 2104, the serial communication interface (SCI) is detected andit is determined whether there is data in the serial communicationinterface (SCI), if yes, step 2105 is executed; if no, step 2101 isreturned.

At step 2105, the system enters a state in which the data is received.

With the power carrier communication system for the electric vehicleaccording to embodiments of the present disclosure, a data transmissionand sharing among various control systems in the electric vehicle can beachieved without increasing internal cable bundles of the vehicle.Moreover, a power carrier communication using the power cable as acommunication medium avoids constructing and investing a newcommunication network, thus reducing the manufacturing cost andmaintenance difficulty.

In one embodiment, the above power system switching between thecharge-discharge function and the driving function is cooled in awater-cooling mode. As shown in FIG. 22, a body of the power system usesan inductor heat dissipation water channel and an IGBT heat dissipationwater channel at the same time, thus solving the heat dissipation andspace occupation problem. The body of the power system is divided intoan upper layer, and a lower layer and a back surface of the IGBT heatdissipation water channel is configured to cool the filtering module.The body is manufactured according to a shape of an inductor and shapedinto an inductor trough 601. Sides of the inductor trough 601 areconfigured to conduct heat to a water channel 602, and finally the waterchannel 602 takes away the heat. In addition, the inductor is fixed by aglue having a high heat conductivity, thus improving a heat conductioncapability and a mechanical strength of the entire structure. The powersystem according to embodiments of the present disclosure is cooled inthe water-cooling mode which has a better heat dissipation effect thanan air-cooling mode. A volume of the filtering module can be reducedunder a same power, and thus a volume and a weight of the entire powersystem can also be reduced.

In addition, embodiments of another aspect of the present disclosureprovide an electric vehicle, comprising the abovementioned power system.The electric vehicle can be charged with a high power by means of athree-phase or single-phase current, such that a user may charge theelectric vehicle conveniently, promptly, anytime and anywhere, thussaving a time cost and satisfying the requirement of persons.

Any procedure or method described in the flow charts or described in anyother way herein may be understood to include one or more modules,portions or parts for storing executable codes that realize particularlogic functions or procedures. Moreover, advantageous embodiments of thepresent disclosure includes other implementations in which the order ofexecution is different from that which is depicted or discussed,including executing functions in a substantially simultaneous manner orin an opposite order according to the related functions. This should beunderstood by those skilled in the art to which embodiments of thepresent disclosure belong.

The logic and/or step described in other manners herein or shown in theflow chart, for example, a particular sequence table of executableinstructions for realizing the logical function, may be specificallyachieved in any computer readable medium to be used by the instructionexecution system, device or equipment (such as the system based oncomputers, the system comprising processors or other systems capable ofobtaining the instruction from the instruction execution system, deviceand equipment and executing the instruction), or to be used incombination with the instruction execution system, device and equipment.As to the specification, “the computer readable medium” may be anydevice adaptive for including, storing, communicating, propagating ortransferring programs to be used by or in combination with theinstruction execution system, device or equipment. More specificexamples of the computer readable medium include but are not limited to:an electronic connection (an electronic device) with one or more wires,a portable computer enclosure (a magnetic device), a random accessmemory (RAM), a read only memory (ROM), an erasable programmableread-only memory (EPROM or a flash memory), an optical fiber device anda portable compact disk read-only memory (CDROM). In addition, thecomputer readable medium may even be a paper or other appropriate mediumcapable of printing programs thereon, this is because, for example, thepaper or other appropriate medium may be optically scanned and thenedited, decrypted or processed with other appropriate methods whennecessary to obtain the programs in an electric manner, and then theprograms may be stored in the computer memories.

It should be understood that each part of the present disclosure may berealized by the hardware, software, firmware or their combination. Inthe above embodiments, a plurality of steps or methods may be realizedby the software or firmware stored in the memory and executed by theappropriate instruction execution system. For example, if it is realizedby the hardware, likewise in another embodiment, the steps or methodsmay be realized by one or a combination of the following techniquesknown in the art: a discrete logic circuit having a logic gate circuitfor realizing a logic function of a data signal, an application-specificintegrated circuit having an appropriate combination logic gate circuit,a programmable gate array (PGA), a field programmable gate array (FPGA),etc.

Those skilled in the art shall understand that all or parts of the stepsin the above exemplifying method of the present disclosure may beachieved by commanding the related hardware with programs. The programsmay be stored in a computer readable storage medium, and the programsinclude one or a combination of the steps in the method embodiments ofthe present disclosure when run on a computer.

In addition, each function cell of the embodiments of the presentdisclosure may be integrated in a processing module, or these cells maybe separate physical existence, or two or more cells are integrated in aprocessing module. The integrated module may be realized in a form ofhardware or in a form of software function modules. When the integratedmodule is realized in a form of software function module and is sold orused as a standalone product, the integrated module may be stored in acomputer readable storage medium.

The storage medium mentioned above may be read-only memories, magneticdisks, CD, etc.

Reference throughout this specification to “an embodiment,” “someembodiments,” “one embodiment”, “another example,” “an example,” “aspecific example,” or “some examples,” means that a particular feature,structure, material, or characteristic described in connection with theembodiment or example is included in at least one embodiment or exampleof the present disclosure. Thus, the appearances of the phrases such as“in some embodiments,” “in one embodiment”, “in an embodiment”, “inanother example,” “in an example,” “in a specific example,” or “in someexamples,” in various places throughout this specification are notnecessarily referring to the same embodiment or example of the presentdisclosure. Furthermore, the particular features, structures, materials,or characteristics may be combined in any suitable manner in one or moreembodiments or examples.

Although explanatory embodiments have been shown and described, it wouldbe appreciated by those skilled in the art that the above embodimentscannot be construed to limit the present disclosure, and changes,alternatives, and modifications can be made in the embodiments withoutdeparting from spirit, principles and scope of the present disclosure.

1. A power system switching between a charge-discharge function and adriving function, comprising: a power battery; a charge-dischargesocket; a bidirectional DC/DC module having a first DC terminalconnected with a first terminal of the power battery and a second DCterminal connected with a second terminal of the power battery, whereinthe first DC terminal is a common DC terminal for an input to and anoutput from the bidirectional DC/DC module; a driving control switchhaving a first terminal connected with the second terminal of the powerbattery and a second terminal connected with a third DC terminal of thebidirectional DC/DC module; a bidirectional DC/AC module having a firstDC terminal connected with the second terminal of the driving controlswitch and a second DC terminal connected with the first terminal of thepower battery; a motor control switch having a first terminal connectedwith an AC terminal of the bidirectional DC/AC module and a secondterminal connected with a motor; a charge-discharge control modulehaving a first terminal connected with the AC terminal of thebidirectional DC/AC module and a second terminal connected with thecharge-discharge socket; and a controller module connected with thedriving control switch, the motor control switch and thecharge-discharge control module respectively, and configured toestablish a path between the power battery and the motor when a currentoperation mode of the power system is a driving mode, and to establish apath between the charge-discharge socket and the power battery when thecurrent operation mode of the power system is a charge-discharge mode.2. The power system according to claim 1, wherein when the currentoperation mode of the power system is the driving mode, the controllermodule controls the driving control switch to turn on to stop thebidirectional DC/DC module, controls the motor control switch to turnon, and controls the charge-discharge control module to turn off.
 3. Thepower system according to claim 1, wherein when the current operationmode of the power system is the charge-discharge mode, the controllermodule controls the driving control switch to turn off to start thebidirectional DC/DC module, controls the motor control switch to turnoff, and controls the charge-discharge control module to turn on tostart the bidirectional DC/AC module.
 4. The power system according toclaim 1, further comprising: a first pre-charging control module havinga first terminal connected with the second terminal of the power batteryand a second terminal connected with the second DC terminal of thebidirectional DC/DC module, and configured to pre-charge a firstcapacitor in the bidirectional DC/DC module and a bus capacitorconnected between the first DC terminal and the third DC terminal of thebidirectional DC/DC module.
 5. The power system according to claim 4,wherein the first pre-charging control module comprises: a first switchhaving a first terminal connected with the second DC terminal of thebidirectional DC/DC module; a first resistor having a first terminalconnected with a second terminal of the first switch and a secondterminal connected with the second terminal of the power battery; and asecond switch, connected in parallel with the first resistor and thefirst switch which are connected in series, wherein when the powersystem starts, the controller module controls the first switch to turnon to pre-charge the first capacitor in the bidirectional DC/DC moduleand the bus capacitor; and when a voltage across the bus capacitor is apredetermined multiple of a voltage of the power battery, the controllermodule controls the first switch to turn off and controls the secondswitch to turn on.
 6. The power system according to claim 1, wherein thebidirectional DC/DC module comprises: a first switching transistor and asecond switching transistor connected in series, and connected betweenthe first DC terminal and the third DC terminal of the bidirectionalDC/DC module, and controlled by the controller module, in which a firstnode is defined between the first switching transistor and the secondswitching transistor; a first diode connected with the first switchingtransistor in inverse-parallel; a second diode connected with the secondswitching transistor in inverse-parallel; a first inductor having afirst terminal connected with the first node and a second terminalconnected with the second terminal of the power battery; and a firstcapacitor having a first terminal connected with the second terminal ofthe first inductor and a second terminal connected with the firstterminal of the power battery.
 7. The power system according to claim 1,further comprising: a leakage current reducing module connected betweenthe first DC terminal and the third DC terminal of the bidirectionalDC/DC module.
 8. The power system according to claim 7, wherein theleakage current reducing module comprises: a second capacitor and athird capacitor, in which the second capacitor has a first terminalconnected with a first terminal of the third capacitor and a secondterminal connected with the third DC terminal of the bidirectional DC/DCmodule, the third capacitor has a second terminal connected with thefirst DC terminal of the bidirectional DC/DC module, and a second nodeis defined between the second capacitor and the third capacitor.
 9. Thepower system according to claim 8, further comprising: a filteringmodule connected between the bidirectional DC/AC module and thecharge-discharge control module.
 10. The power system according to claim9, further comprising: a filtering control module connected between thesecond node and the filtering module, in which when the currentoperation mode of the power system is the driving mode, the controllermodule controls the filtering control module to turn off.
 11. The powersystem according to claim 9, further comprising: an EMI-filter moduleconnected between the charge-discharge socket and the charge-dischargecontrol module.
 12. The power system according to claim 11, furthercomprising: a second pre-charging control module connected with thecharge-discharge control module in parallel and configured to pre-chargea capacitor in the filtering module.
 13. The power system according toclaim 1, wherein the charge-discharge control module comprises: athree-phase switch and/or a single-phase switch configured to implementa three-phase charge-discharge or a single-phase charge-discharge. 14.An electric vehicle comprising a power system, the power systemcomprising: a power battery; a charge-discharge socket; a bidirectionalDC/DC module having a first DC terminal connected with a first terminalof the power battery and a second DC terminal connected with a secondterminal of the power battery, wherein the first DC terminal is a commonDC terminal for an input to and an output from the bidirectional DC/DCmodule; a driving control switch having a first terminal connected withthe second terminal of the power battery and a second terminal connectedwith a third DC terminal of the bidirectional DC/DC module; abidirectional DC/AC module having a first DC terminal connected with thesecond terminal of the driving control switch and a second DC terminalconnected with the first terminal of the power battery; a motor controlswitch having a first terminal connected with an AC terminal of thebidirectional DC/AC module and a second terminal connected with a motor;a charge-discharge control module having a first terminal connected withthe AC terminal of the bidirectional DC/AC module and a second terminalconnected with the charge-discharge socket; and a controller moduleconnected with the driving control switch, the motor control switch andthe charge-discharge control module respectively, and configured toestablish a path between the power battery and the motor when a currentoperation mode of the power system is a driving mode, and to establish apath between the charge-discharge socket and the power battery when thecurrent operation mode of the power system is a charge-discharge mode.15. The power system according to claim 14, wherein when the currentoperation mode of the power system is the driving mode, the controllermodule controls the driving control switch to turn on to stop thebidirectional DC/DC module, controls the motor control switch to turnon, and controls the charge-discharge control module to turn off. 16.The electric vehicle according to claim 14, wherein when the currentoperation mode of the power system is the charge-discharge mode, thecontroller module controls the driving control switch to turn off tostart the bidirectional DC/DC module, controls the motor control switchto turn off, and controls the charge-discharge control module to turn onto start the bidirectional DC/AC module.
 17. The electric vehicleaccording to claim 14, wherein the power system further comprises: afirst pre-charging control module having a first terminal connected withthe second terminal of the power battery and a second terminal connectedwith the second DC terminal of the bidirectional DC/DC module, andconfigured to pre-charge a first capacitor in the bidirectional DC/DCmodule and a bus capacitor connected between the first DC terminal andthe third DC terminal of the bidirectional DC/DC module.
 18. The powersystem according to claim 17, wherein the first pre-charging controlmodule comprises: a first switch having a first terminal connected withthe second DC terminal of the bidirectional DC/DC module; a firstresistor having a first terminal connected with a second terminal of thefirst switch and a second terminal connected with the second terminal ofthe power battery; and a second switch, connected in parallel with thefirst resistor and the first switch which are connected in series,wherein when the power system starts, the controller module controls thefirst switch to turn on to pre-charge the first capacitor in thebidirectional DC/DC module and the bus capacitor; and when a voltageacross the bus capacitor is a predetermined multiple of a voltage of thepower battery, the controller module controls the first switch to turnoff and controls the second switch to turn on.
 19. The power systemaccording to claim 14, wherein the bidirectional DC/DC module comprises:a first switching transistor and a second switching transistor connectedin series, and connected between the first DC terminal and the third DCterminal of the bidirectional DC/DC module, and controlled by thecontroller module, in which a first node is defined between the firstswitching transistor and the second switching transistor; a first diodeconnected with the first switching transistor in inverse-parallel; asecond diode connected with the second switching transistor ininverse-parallel; a first inductor having a first terminal connectedwith the first node and a second terminal connected with the secondterminal of the power battery; and a first capacitor having a firstterminal connected with the second terminal of the first inductor and asecond terminal connected with the first terminal of the power battery.20. The power system according to claim 14, wherein the power systemfurther comprises: a leakage current reducing module connected betweenthe first DC terminal and the third DC terminal of the bidirectionalDC/DC module.